In spite of a large amount of misinformation which has been presented to the public, there is convincing scientific and technical information available that it is possible for most people to survive a full scale exchange of nuclear, biological or chemical weapons, or disaster caused by an industrial accident provided that proper advance preparations are made.
It is acknowledged that there would be little incentive for an individual to survive such a nuclear holocaust or biological disaster if, as a result, all life on earth were doomed to extinction or marginal existence. However, the National Academy of Sciences (NAS) has produced extensive reports on the atmospheric effects from various war scenarios, which contradict any such idea. In reality, therefore, the question today is not whether persons can survive a nuclear, biological and chemical warfare or disaster agents, but whether people have the will and determination to prepare for survival.
A number of underground disaster shelters have been developed in preparation of such a disaster. The typical backyard, or personal, shelter has the capability of providing shelter for a small number of people, such as a family unit and incorporates features to protect its occupants against some of the effects of nuclear weapons. However, many shelters have oxygen tanks to provide the shelterists with fresh, uncontaminated air. Further, even in shelters that do include liquid oxygen tanks, these tanks are seldom large enough to provide sufficient oxygen to such a shelter for extended periods of time. Therefore, when oxygen tanks are depleted, or malfunction, shelterists are forced to breath air from outside the shelter, which may be contaminated by a number of different agents. Therefore, there is a need to provide an air sterilization system that will purify contaminated air entering a disaster shelter.
It is recognized that a number of air purification systems have been designed to filter the air in a room in order to remove contaminants from breathable air. For example, U.S. Pat. No. 5,207,877 issued May 3, 1993, describes a method for the purification of air in which air polluted with potentially harmful chemical and biological matter is purified and pollutants degraded to less hazardous substances by a combined chemical and electrical process.
Although this invention purifies and destroys most potentially harmful airborne chemicals, microorganisms and other biologicals both by chemical and electrochemical means, it has a number of drawbacks. First, the system does not filter harmful nuclear fallout, and therefore is ineffective in the event of a nuclear disaster. Second, it is directed at purifying the air in a room where a known contaminant is found and therefore, neither filters incoming air nor maintains a closed environment to prevent outside air from entering a room. Third, the electrochemical reaction utilized by this system relies on available ions and bondable compounds to attract the hazardous and undesirable contaminants. Accordingly, this method will eventually cease to function properly due to the lack of available bondable ions and compounds. In such an event, the filtration system will not function properly unless the used chemicals are removed and fresh chemical replenished. Finally, the need to remove and replenish chemicals creates another potential hazard for the average person due to the risk of accidents during handling and storage of the spent and unspent chemical. For these reasons this method of air purification is not suitable for use in protecting from nuclear, biological and chemical disasters.
U.S. Pat. No. 4,337,071 issued Jun. 29, 1982 describes an on-site apparatus that produces cryogenic temperatures used to remove, by condensations all pollutants in the air so that an ultra clean air supply is obtained for human consumption in the interior of living enclosures, such as automobiles, homes, offices, hospitals etc. The apparatus can recycle air in the enclosure, i.e. resupply the oxygen consumed by the human being and remove the carbon dioxide produced by respiration. Cold traps (filters) of different cryogenic temperatures are built into the system to condense the pollutants of different condensation temperatures. The condensed pollutants can be disposed of by periodical defrost and purge of the system.
Although this system would allow a sealed room to maintain breathable atmosphere, it also has a number of drawbacks. First, this system does not contain a filter capable of removing nuclear fallout, biological hazards and dangerous chemicals from the air. Second, this system maintains a closed environment by recycling air, the system does not accomplish the decontamination process which is crucial for maintaining a safe environment in the event of a full scale exchange of nuclear, biological or chemical weapons, or disaster caused by an industrial accident. Third, the large amount of power required to maintain the temperatures required by these systems cannot be supplied for long by existing battery systems. Therefore, such a system will be ineffective in circumstances where power to a shelter is not functioning.
U.S. Pat. No. 5,626,820 issued May 6, 1997 describes a clean room air-filtering device. This device features a clean room and chemical air filter suitable for use in the air handling system of the clean room directly upstream of high-efficiency particulate air (HEPA) filters. This device includes a HEPA filter (high efficiency particulate air filter), in addition to chemical filters targeted for the removal of the specific contaminants contained in the various air streams inside a clean room. The clean room air filter is designed to remove chemicals and other gas-phase contaminants created from within the clean room itself during the regular activities occurring in the manufacture of semiconductor devices. In addition, this device includes a processing station that generates a gas-phase contaminant in which the activated carbon particles are preferably selected to remove contaminant produced by the processing station.
This system is also ill suited for use in disaster situations. First, this air handling system preferably includes a make-up air system for drawing air from an atmosphere outside of the clean room, and is subject to contamination by an ambient contaminant. As this make-up air is made to air is passed through borosilicate filter material, rather than more efficient HEPA and/or charcoal filters, this make-up air may act to contaminate the interior air. Second, as this filter is directed to preventing dust and other airborne contaminants from interfering with manufacturing operations, it is not suited for the protection of humans from nuclear fallout, chemical or biological disasters that occur outside the processing station. Finally, this system does not include any means of determining whether contaminants are present within the air entering the system and, therefore, would need to be continuously employed to be effective.
U.S. Pat. No. 5,399,319 issued Mar. 21, 1995 describes a portable, convertible apparatus for creating either a negative pressure or a positive pressure in and filtering the air in a room. Within the airflow path, a HEPA filter is located in the device. This device will maintain a negative pressure in a room thereby preventing the air from inside the room where the device is active from escaping the room. Allowing only non infected air from outside the room to enter the room where the device is located. Alternatively, the device can function to maintain clean air inside a room so that if a door in the room opens, clean air will rush out of the room thereby preventing contaminated air from rushing into the room.
Although this device is useful in creating either a positive or negative pressure inside a room and thus maintaining either the desired clean air or infected air inside a room, the device does not filter air from the outside. This device contains one filter, a HEPA filter, that is capable of removing small quantities of contaminants that accidental entered the room, but is not useful in removing contaminants from the air outside of the room, which is needed in order to filter air entering a shelter. This device does not take air directly from the atmosphere, or outside of the room, and filter contamination, rather the device filters only that air already present in the closed room. Therefore, it is not designed to maintain a clean air environment for an undefined period of time and provide adequate air for human survival. Finally, this device would not provide human protection from atmospheric contaminants in the event of a nuclear, biological or chemical attack or accident.
Finally, the inventor of the present invention invented the life cell disclosed and claimed in U.S. Pat. No. 6,296,693, which is directed at filtering contaminated air entering a room in the event of a disaster. This life cell includes a contaminant detector, for detecting the presence of a contaminant in a volume of air, and an air filtration system for removing contaminants from the volume of air. The air filtration system of the life cell includes an air inlet, HEPA filter in fluid communication with the air inlet for removing particulate contaminants from the volume of air, and a carbon filter in fluid connection with the HEPA filter for removing chemical and biological contaminants from the volume of air. A blower is placed in fluid communication with the carbon filter and HEPA filter and acts to draw the volume of air from the air inlet, through the HEPA filter and carbon filter, and exhaust the volume of air such that a positive pressure is created. The preferred life cell includes a carbon filter made up of two layers of foam, an activated carbon filter medium, and a Whetlerite carbon filter medium. Finally, the preferred life cell is disposed within a self-contained housing and includes a battery bank, a light, a radio, and a communications device.
The life cell disclosed in U.S. Pat. No. 6,296,693 is effective at filtering air entering a room of a home of most chemical and biological contaminants. However, because the life cell needed to create a positive pressure within a room, it could not be sealed to prevent ingress or egress of air from an enclosed space, like a shelter cell. In addition, the life cell did not protect against many strains of bacteria and airborne viruses. Finally, the two stage filtering design, where the HEPA filter and chemical filter were separated, increased the size of the life cell such that it could not easily fit within the entranceway of a conventional shelter. Therefore it does not solve all of the problems facing shelterists.
Therefore, there is a need for an air sterilization system that provides human protection from atmospheric contaminants in the event of a nuclear, biological or chemical attack or accident, that purifies air directly from the atmosphere, that may be effectively operated by batteries, that includes a means for determining whether contaminants are present within the air entering the system, that does not require that used chemicals are removed and fresh chemical replenished, that both purifies incoming air and exhausts spent air, heat and moisture from a shelter, that may be sealed to prevent ingress or egress of air from an enclosed space, and that protects against all known strains of bacteria and airborne viruses.